The present invention relates to an image forming apparatus and an image forming system incorporating the same.
An image forming apparatus, such as a laser beam printer, has already been well known. Such an image forming apparatus comprises, for example, an image carrier for carrying a latent image thereon; developing devices, each of which develops the latent image carried on the image carrier with use of a developing agent; a rotary member having a plurality of loading sections allowing removable loading of the developing devices; and a motor for rotating the rotary member.
When an image signal is transmitted from an external apparatus, such as a host computer, to the image forming apparatus, the rotary member is rotated by driving force of the motor, so that the developing device is placed at the development position opposing the image carrier. The latent image carried on the image carrier is developed with the developing agent stored in the developing device, to thus form a visible image, and the visible image is transferred onto a medium, thereby eventually forming an image. Such an image forming apparatus is disclosed in Japanese Patent Publication No. 5-241418A, for example.
Although the rotary member repeats rotation and stopping, some types of the motor are provided with not only the function of rotating the rotary member, but also the function of retaining the rotary member at a stop position when the rotary member is at a standstill.
However, when the motor retains the rotary member at the stop position, power is supplied to the motor. Therefore, electric power is consumed. Hence, a measure for suppressing the electric power consumed by the motor when the motor retains the rotary member at the stop position is requested.